Re: [vfio-users] setting up virtual disks
On Tue, 2017-03-28 at 13:51 +0100, Bronek Kozicki wrote: > As you can see, I've setup the controller with 4 queues and 3 devices, > of which 2 are ZFS ZVOL and 1 is raw block device. I also have plenty of > spare CPUs (2 sockets, 16 cores, 32 threads), so I'm expecting that > having 4 queues will aid IO performance. OK, I'll try and work with that. poc ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On Tue, 2017-03-28 at 16:01 +0200, Laszlo Ersek wrote: > On 03/28/17 15:41, Patrick O'Callaghan wrote: > > On Tue, 2017-03-28 at 15:08 +0200, Laszlo Ersek wrote: > > > On 03/28/17 14:21, Patrick O'Callaghan wrote: > > > > On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: > > > > > I recommend the following setup: > > > > > > > > > > - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer > > > > > > > > I'm interested in why someone would prefer one over the other. Can you > > > > explain? > > > > > > I prefer virtio-scsi because it supports thin provisioning (UNMAP scsi > > > operation); it lets me conserve space in host filesystems that support > > > discard (such as ext4 or xfs, for example -- there may be more). Given > > > the right configuration, if you delete files in your Windows 8 or > > > Windows 10 VM, the space is eventually released on the host filesystem. > > > > OK, thanks. > > > > > With virtio-blk, the software stack is less featureful and thereby > > > thinner, which is said by some to lead to better performance. Also, as > > > far as I know, dataplane is only available for virtio-blk at the moment, > > > it is in progress for virtio-scsi. (I could be out of date on that > > > though.) YMMV. > > > > No idea what that is. As I'm not provisioning multiple high-load > > servers, does this matter to me? > > I couldn't give you more authoritative documentation than what google > turns up, so please go ahead and search for it yourself. Personally, I > have never ever set up virtio-blk dataplane, in my short or long term > guests (some of which use GPU or other device assignment as well), and I > have no complaints about IO performance. (I too don't run production > servers, like you.) The bottleneck on my laptop has always been SSD > capacity (even with two SSDs), which virtio-scsi (with unmap/discard > enabled) has remedied impeccably. I guess, if you haven't complained to > yourself about IO performance, don't bother with dataplane. That's fine, thanks. poc ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On 03/28/17 15:41, Patrick O'Callaghan wrote: > On Tue, 2017-03-28 at 15:08 +0200, Laszlo Ersek wrote: >> On 03/28/17 14:21, Patrick O'Callaghan wrote: >>> On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: I recommend the following setup: - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer >>> >>> I'm interested in why someone would prefer one over the other. Can you >>> explain? >> >> I prefer virtio-scsi because it supports thin provisioning (UNMAP scsi >> operation); it lets me conserve space in host filesystems that support >> discard (such as ext4 or xfs, for example -- there may be more). Given >> the right configuration, if you delete files in your Windows 8 or >> Windows 10 VM, the space is eventually released on the host filesystem. > > OK, thanks. > >> With virtio-blk, the software stack is less featureful and thereby >> thinner, which is said by some to lead to better performance. Also, as >> far as I know, dataplane is only available for virtio-blk at the moment, >> it is in progress for virtio-scsi. (I could be out of date on that >> though.) YMMV. > > No idea what that is. As I'm not provisioning multiple high-load > servers, does this matter to me? I couldn't give you more authoritative documentation than what google turns up, so please go ahead and search for it yourself. Personally, I have never ever set up virtio-blk dataplane, in my short or long term guests (some of which use GPU or other device assignment as well), and I have no complaints about IO performance. (I too don't run production servers, like you.) The bottleneck on my laptop has always been SSD capacity (even with two SSDs), which virtio-scsi (with unmap/discard enabled) has remedied impeccably. I guess, if you haven't complained to yourself about IO performance, don't bother with dataplane. Laszlo ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On Tue, 2017-03-28 at 15:08 +0200, Laszlo Ersek wrote: > On 03/28/17 14:21, Patrick O'Callaghan wrote: > > On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: > > > I recommend the following setup: > > > > > > - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer > > > > I'm interested in why someone would prefer one over the other. Can you > > explain? > > I prefer virtio-scsi because it supports thin provisioning (UNMAP scsi > operation); it lets me conserve space in host filesystems that support > discard (such as ext4 or xfs, for example -- there may be more). Given > the right configuration, if you delete files in your Windows 8 or > Windows 10 VM, the space is eventually released on the host filesystem. OK, thanks. > With virtio-blk, the software stack is less featureful and thereby > thinner, which is said by some to lead to better performance. Also, as > far as I know, dataplane is only available for virtio-blk at the moment, > it is in progress for virtio-scsi. (I could be out of date on that > though.) YMMV. No idea what that is. As I'm not provisioning multiple high-load servers, does this matter to me? poc ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On 03/28/17 14:21, Patrick O'Callaghan wrote: > On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: >> I recommend the following setup: >> >> - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer > > I'm interested in why someone would prefer one over the other. Can you > explain? I prefer virtio-scsi because it supports thin provisioning (UNMAP scsi operation); it lets me conserve space in host filesystems that support discard (such as ext4 or xfs, for example -- there may be more). Given the right configuration, if you delete files in your Windows 8 or Windows 10 VM, the space is eventually released on the host filesystem. With virtio-blk, the software stack is less featureful and thereby thinner, which is said by some to lead to better performance. Also, as far as I know, dataplane is only available for virtio-blk at the moment, it is in progress for virtio-scsi. (I could be out of date on that though.) YMMV. Laszlo ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
Here are relevant parts of my VM definition: As you can see, I've setup the controller with 4 queues and 3 devices, of which 2 are ZFS ZVOL and 1 is raw block device. I also have plenty of spare CPUs (2 sockets, 16 cores, 32 threads), so I'm expecting that having 4 queues will aid IO performance. B. -- Bronek Kozicki b...@spamcop.net On Tue, 28 Mar 2017, at 01:21 PM, Patrick O'Callaghan wrote: > On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: > > I recommend the following setup: > > > > - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer > > I'm interested in why someone would prefer one over the other. Can you > explain? > > poc > > ___ > vfio-users mailing list > vfio-users@redhat.com > https://www.redhat.com/mailman/listinfo/vfio-users ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On Tue, 2017-03-28 at 11:47 +0200, Laszlo Ersek wrote: > I recommend the following setup: > > - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer I'm interested in why someone would prefer one over the other. Can you explain? poc ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On 03/28/17 02:04, Alex Williamson wrote: > On Mon, Mar 27, 2017 at 5:46 PM, Stibnite wrote: > >> >> I'm trying to setup a disk passthrough on virt-manager using the guide >> outlined but the disk device does not appear in the windows installation >> window. I'm sure i'm missing something obvious but i can't seem to get it >> working. https://access.redhat.com/documentation/en-US/Red_Hat_ >> Enterprise_Linux/6/html/Virtualization_Administration_ >> Guide/sect-Virtualization-Adding_storage_devices_to_ >> guests-Adding_hard_drives_and_other_block_devices_to_a_guest.html >> >> here's an excerpt of my xml file. >> >> >> /usr/sbin/qemu-system-x86_64 >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> > function='0x0'/> >> >> > > > Windows doesn't ship with virtio drivers, just like it doesn't ship with > drivers for various other one-off storage controllers. You'll need to > install drivers for the disk on the virtio controller to show up > https://fedoraproject.org/wiki/Windows_Virtio_Drivers I recommend the following setup: - hard disk(s): virtio-blk or virtio-scsi disk, as you prefer - Windows installer ISO: virtio-scsi CD-ROM - virtio-win driver ISO: *separate* IDE CD-ROM (or SATA, if you use Q35) Windows installation will proceed off of the virtio-scsi CD-ROM far enough for you to select the *other* (IDE or SATA) CD-ROM, with the virtio-win drivers, for loading drivers into the installer. After which point the Windows installer will see both the destination hard disk, and the installer CD-ROM (again). Search the Wiki article referenced by Alex for the string virtio-win iso under "Direct download". The ISO image linked there is what you need for the above method. Thanks Laszlo ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
Re: [vfio-users] setting up virtual disks
On Mon, Mar 27, 2017 at 5:46 PM, Stibnite wrote: > > I'm trying to setup a disk passthrough on virt-manager using the guide > outlined but the disk device does not appear in the windows installation > window. I'm sure i'm missing something obvious but i can't seem to get it > working. https://access.redhat.com/documentation/en-US/Red_Hat_ > Enterprise_Linux/6/html/Virtualization_Administration_ > Guide/sect-Virtualization-Adding_storage_devices_to_ > guests-Adding_hard_drives_and_other_block_devices_to_a_guest.html > > here's an excerpt of my xml file. > > > /usr/sbin/qemu-system-x86_64 > > > > > > > > > > > > > > > > > > > > >function='0x0'/> > > Windows doesn't ship with virtio drivers, just like it doesn't ship with drivers for various other one-off storage controllers. You'll need to install drivers for the disk on the virtio controller to show up https://fedoraproject.org/wiki/Windows_Virtio_Drivers ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
[vfio-users] setting up virtual disks
I'm trying to setup a disk passthrough on virt-manager using the guide outlined but the disk device does not appear in the windows installation window. I'm sure i'm missing something obvious but i can't seem to get it working. https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/sect-Virtualization-Adding_storage_devices_to_guests-Adding_hard_drives_and_other_block_devices_to_a_guest.html here's an excerpt of my xml file. /usr/sbin/qemu-system-x86_64 ___ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
